In honor of Oreo's 100th birthday, Lady Antebellum showed up at The Grove on Tuesday morning to belt out a few of their hit tunes in a surprise free concert for one of America's favorite cookies!

Before singing "Happy Birthday" to a giant Oreo (yum!) the Grammy winning band kicked off a Happy Birthday flash mob, which was just one of seven similar celebrations that took place across the country in honor of the delicious treat.